166 MORPHOLOGY OF FERTILIZATION 



REFERENCES 



Afzelius, B. A. 1955. The fine structure of the sea urchin spermatozoa 

 as revealed by the electron microscope. Z. Zellforsch., 42, 134-48. 



Bm-gos, M. H., and D. W. Fawcett. 1955. Studies on the fine structure 

 of the mammalian testis. I. Differentiation of the spermatids in the 

 cat (Fehs domestica). /. Biophys. Biochem. Cyt., I, 287-300. 



Burgos, M. H., and D. W. Fawcett. 1956. An electron microscope 

 study of spermatid differentiation in the toad, Btifo arenarum Hen- 

 sel. /, Biophys. Biochem. Cyt., 2, 223-40. 



Chambers, R. 1923. The mechanism of sperm entrance into the star- 

 fish egg. /. Gen. Physiol, 5, 821-29. 



Chambers, R. 1930. The manner of sperm entry in the starfish egg. 

 Biol Bull, 58, 344-69. 



Clermont, Y., R. E. Glegg, and C. P. Leblond. 1955. Presence of carbo- 

 hydrates in the acrosome of the guinea pig spermatozoon. Exptl 

 Cell Research, 8, 453-58. 



Colwin, A. L., and L. H. Colwin. 1953. The normal embryology of 

 Saccoglossus kowalevskii ( Enteropneusta ) . /. Morphol, 92, 401-54. 



Colwin, A. L., and L. H. Colwin. 1955a. Sperm entry and the acrosome 

 filament (Holothuria atra and Asterias amurensis). }. Morphol, 97, 

 543-68. 



Colwin, A. L., and L. H. Colwin. 1955b. Concerning the spermato- 

 zoon and fertilization in the egg of Sabellaria vulgaris. Biol Bull, 

 109, 357. 



Colwin, L. H., and A. L. Colwin. 1954a. Fertilization changes in the 

 membranes and cortical granular layer of the egg of Saccoglossus 

 kowalevskii (Enteropneusta). /. Morphol, 95, 1-46. 



Colwin, L. H., and A. L. Colwin. 1954b. Sperm penetration and the 

 fertilization cone in the egg of Saccoglossus kowalevskii (Enterop- 

 neusta). /. Morphol, 95, 351-72. 



Colwin, L. H., and A. L. Colwin. 1955c. The spermatozoon and sperm 

 entry in the egg of the holothurian, Thy one briar ens. Biol Bull, 

 109, 357. 



Colwin, L. H., and A. L. Colwin. 1955d. Some factors related to 

 sperm entry in two species of Asterias. Biol Bull, 109, 357. 



Colwin, L. H., and A. L. Colwin. 1956. The acrosome filament and 



